Transcript Efficacy of pour-on dewormers on weight gain and fecal egg

Efficacy of pour-on dewormers on
weight gain and fecal egg count in
Hawaiian stocker cattle
Jonathon Beckett1, Tim Richards2,
Craig Reinemeyer3
1Animal Science Department, Cal Poly
State University, Kahua Ranch2, East
Tennessee Clinical Research3
What is a Parasite?
 The
Random House Dictionary defines
it as an organism that lives on or within
a plant or animal of a different species,
from which it obtains nutrients.
Parasites of Concern
Bunostomum phlebotomum (Cattle Hookworm)
•Causes itching of the leg and feet
• Irritate stomach and intestines
• Feed on blood in the intestinal wall
• Causes bloody, tar colored diarrhea
Fasciola hepatica (Common Liver Fluke)
•Live in the bile ducts of the liver, and gallbladder
• Animals experience anemia and decreased growth
• Usually results in condemnation of the liver at slaughter
Strongyloides papillosus (Intestinal threadworm)
•Most common in young calves
• Causes intermittent diarrhea, loss of appetite, and weight
Parasites of Concern
Cooperia spp (Cattle Bankrupt worm)
•Lives in the Small Intestine
•Animals exhibit poor utilization of feed, taking a long
time to reach market weight
Ostertagia ostertagia (Brown Stomach Worm)
•Affected cattle not only lose weight but often die
• Cells damaged by the parasite are replaced by rapidly
dividing cells that lack function
•The most commonly found and economically important
internal parasite
Toxocara vitulorum (Large Roundworm)
•Live in the Small Intestine
• Found especially in warm climates
• can travel through the lung and cause pneumonia
• Compete with host for food , causing diarrhea and weight loss
Clinical Parasitism

Diarrhea

Anemia

Rough hair coat

“Pot bellied” appearance

“Bottle jaw”

Less common
Subclinical Parasitism

Decreased milk production

Poor performance

More susceptible to disease

Infertility

Unthrifty
We Deworm Cattle For
Only One Reason
 FOR
THE MONEY
Benefits
of Deworming

Increased productivity

Increased efficiency

Better immune status

Increased breeding efficiency

Reduced pasture contamination
Importance of fecal egg counts?
 Most
commonly used technique
 Usefulness depends on its precision
and accuracy
 Requires knowledge of parasite biology
in area, experience with levels that are
indicative of economic impact in a given
situation
Importance of Larval Cultures
 Very
few parasitologist are able to
differentiate between different genera of
the parasite eggs
 Nematodirus is only “easy one”
 Larval cultures let eggs hatch then the
worms are identified
Macrocyclic Lactones
 Avermectins
–
–
–
–
–

Ivermectin (Ivomec)
Doramectin (Dectomax)
Eprinomectin (Eprinex
Look alikes
Generic
Milbemycins
– Moxidectin (Cydectin)
Types of Administration
 Injectable
 Drench
– Advantage – Easy to
administer
– Disadvantage – Can create
problems in the meat
– Disadvantage – Must be redosed every 60 days

Pour-On
– Advantage – Very quick to
administer
– Advantage – Noninvasive
administration
– Disadvantage – Must be redosed every 60 days
– Advantage – Very quick to
administer (not as quick as
Pour-On)
– Disadvantage – Must be redosed every 60 days
– Disadvantage – Cow can spit
out most of the product

Bolus
– Advantage – Dosed only once
in the cow’s life
– Disadvantage – Much longer
administration time
– Disadvantage – Administration
requires training
Hypothesis
The
effective
drug
in
pour-on
dewormers will affect growth and
parasite infection throughout the
grazing season in stocker cattle.
Protocol
Transported
to Harvested
Transported
Dewormed
Transported to
Redewormed
Feedyard,
at IBP,
by boat to with
Swanton
Redewormed
Dewormed
Bruneau, ID Boise, ID
CanadaDectomax
Pacific Ranch
A
Cydectin
B
Dectomax
C
Eprinex
D
Ivomec
E
Control
156
-60
-21-14 0
70
Days
126
330
Average Daily Gain
Day 0-105
2.5
a
a
a
a
2
b
1.5
1
0.5
0
Cydectin
Dectomax
Eprinex
Ivomec
Control
Average Body Weight
Day 105
+36.1
540
+32.8
+31.6
+27.6
530
520
510
500
490
480
Cydectin
Dectomax
Eprinex
Ivomec
Control
Total Fecal Egg Count
350
EPG
300
250
Cydectin
200
Dectomax
Eprinex
150
Ivomec
100
Control
50
0
0
28
70
105
Day of Study
131
Fecal Egg Counts
Days
Treatment
0
28
70
105
126
Cydectin
0.7
4.8b
39.2b
1.6c
12.9c
Dectomax
0.8
15.6b
75.2a
2.1c
11.2c
Eprinex
2.0
1.1c
54.2ab
7.4b
21.2b
Ivomec
0.7
1.1c
86.0a
5.6b
13.8bc
Control
1.7
292.1a
57.9ab
40.2a
45.5a
ab
Numbers with differing superscripts within a column differ significantly (p<.05)
Dewormed
Redewormed
Carcass Weights
700
695
690
685
680
675
670
Cydectin
Dectomax
Eprinex
Ivomec
Control
Yield Grade
3.5
3.4
3.3
3.2
3.1
3
Cydectin
Dectomax
Eprinex
Ivomec
Control
Backfat
0.6
0.58
0.56
0.54
0.52
0.5
Cydectin
Dectomax
Eprinex
Ivomec
Control
Ribeye Area
12
a
11.8
ab
ab
11.6
ab
b
11.4
11.2
11
Cydectin
Dectomax
Eprinex
Ivomec
Control
Marbling Score
735
730
725
720
715
710
705
700
695
Cydectin
Dectomax
Eprinex
Ivomec
Control
Yield Grade 1 & 2’s
45%
40%
35%
30%
25%
20%
15%
10%
5%
0%
Cydectin
Dectomax
Eprinex
Ivomec
Control
What does this mean?
 It
is important to deworm
 Eprinex and Cydectin equally resulted in
maximal growth
 Ivomec is the weakest against internal
parasites
 Without adequate forage, no dewormer
is fully effective
What does this mean?
 Effect
of dewormer during stocker
phase is not significant at slaughter but
effects are visible
– Take advantage of cheap gain during
stocker phase rather than pay more for the
gain in the feedyard
What does this mean?
 Other
factors must be considered when
selecting a dewormer
– Cost
– Persistency of Protection
– Ease of Administration
– Rain Fastness
– Flame Resistance
– Customer Service
Acknowledgements
Ranch – Thank you for allowing Cal
Poly to conduct the trial on their cattle
 Bruneau Cattle Company – Accommodating
the feedlot phase
 2001 Swanton Pacific Stocker Enterprise
group for participating in the data collection
and organization of the trial
 Brian Wetzel – Cal Poly Alumni for initiating
this line of research as his senior project
 Kahua